You'll find out (1940) http://www.imdb.com/title/tt0033283/
An early voice effect using the same principle of the throat as a filter was the Sonovox. Instead of a throat microphone modulating a guitar signal, it used small loudspeakers attached to the performer's throat.
http://en.wikipedia.org/wiki/Sonovox#Sonovox
Predecessor of the Vocoder.